mkfifo: permissions of an existing file are changed after FIFO creation fails

NVD Description

When `mkfifo()` fails (e.g. target already exists), the code shows an error but is missing a `continue;`, so it falls through to `fs::set_permissions` and changes the permissions of the pre-existing file to the default FIFO mode (`0o666` & umask -> `0644`). ``` $ touch secret; chmod 000 secret $ coreutils mkfifo secret fifo3 fifo4 mkfifo: cannot create fifo 'secret': File exists $ ll secret # uutils: prw-r--r-- secret # changed to 644 (GNU leaves it 000) ``` **Impact:** an attacker (or user error) can relax permissions on sensitive owner-only files such as SSH private keys, exposing them to other users. Recommendation: add `continue;` after the error. **Remediation:** Acknowledged by Canonical; fixed in PR #10376. --- _Reported by Zellic in the *uutils coreutils Program Security Assessment* (prepared for Canonical, Jan 20 2026), audited commit `3a07ffc5a9bd4c283e75afa548ba1f1957bad242`. Finding 3.8. Credit: Zellic._ _Upstream tracking issue: https://github.com/uutils/coreutils/issues/10020 · CVE-2026-35341_

Affected Packages (1)